Message Oracle RMAN-06442 - enter UPGRADE CATALOG command again to confirm catalog upgrade

ERRORenter UPGRADE CATALOG command again to confirm catalog upgrade
CAUSEThe UPGRADE CATALOG command alters the recovery catalog schema. Although the recovery catalog is designed to be compatible with older versions of the Recovery Manager (RMAN), it is possible that an upgrade will remove support for older versions of RMAN.
ACTIONIf you really want to upgrade the recovery catalog, then enter the UPGRADE CATALOG command again. If you are not going to use an older version of RMAN with this recovery catalog, then compatibility is not an issue. If you plan to also continue using an older version of RMAN with this recovery catalog then, before upgrading, consult the Migration Guide for the current Oracle release to determine if upgrading to the current version of the recovery catalog will remove support for older versions of RMAN.